Comparison of continuous cardiac output measurement methods: Non-invasive estimated CCO using pulse wave transit time and CCO using thermodilution

Background: esCCO™ (estimated continuous cardiac output, Nihon Kohden, esCCO™) is a new cardiac output measurement system which uses pulse wave transit time to calculate cardiac output continuously and non-invasively. One of the most commonly used methods to monitor cardiac output is continuous cardiac output CCO (Edwards Lifesciences) which has an accuracy equivalent to that of thermodilution method. Methods: We compared esCCO to CCO in 67 operating room patients and 128 intensive care unit patients. CCO and esCCO were measured simultaneously in patients with a pulmonary artery catheter inserted after admission to the operating room or intensive care unit. Results: CCO and esCCO showed a high correlation with a correlation coefficient of 0.84 in 496 total data points, and 95% limits of agreement between these two methods were -2.49 to 2.35 l·min^-1. Conclusions: This result suggests that esCCO could be used to measure cardiac output accurately and non-invasively in different cases.